1. Field of the Invention
This invention relates to a coping apparatus utilizing a circular saw blade that is rotated by an arbor coupled to a motor to perform a wood cutting operation while the position of cutting edge of the saw blade is controllably positioned by movement of a stylus along a template in which the cutting operation closely approximately the width of the stylus.
2. Description of the Prior Art
It is known in the art to cope molding by first forming a traced outline as a negative image reproduction of the decorative face profile and then using a coping saw to cut about the end grain of the molding along the traced outline so that the end portion of the molding bears the decorative profile of the molding. The coped end of the molding being so shaped can butt against the face of a separately installed piece of such molding to present an attractive junction, usually at an inside corner. The coping operation however, is laborious and time consuming requiring a degree of extra care for the wood cutting operation. In such a coping operation there is the ever present problem that cut edge is imprecise so that it may not fit snugly against an abutting face of the molding so as to achieve the required appearance. Sometimes, for example, the straight cut formed by the coping saw is angled less than perpendicular to the face whereby the butt face of the coped portion does not seat squarely against the molded face. In other circumstances, even though the coping operation is accurately preformed, the corner of the walls may not be perpendicular whereby a mismatch of the cope end with the holding face occurs.
The present invention departs from the hand cutting method of coping as described above as well as known apparatus is known for coping by forming a coped end on a molding which presents contact edge that can fit snugly against the face of an adjoining edge. The contact edge is formed by an undercut, preferably circular, derived from the use of a circular saw blade.
It is known, for example, from U.S. Pat. No. 4,249,446 to form a coping tracing operation wherein the wood cutting device consists of a round bandsaw blade that is trained about a system of pulleys one of which is driven so that a length of the blade spanning a gap between two pulleys confronts the edge of the molding for the coping operation. The coping apparatus requires that a piece of molding is used as a specimen to define the profile that is to be coped in the end of a second piece of molding. The round bandsaw blade is moved in the direction of its length at a site between the two pieces of molding. The arrangement is such that a specimen and a workpiece are on opposite sides of the blade. The tracing operation causes a movement in a given instance into a valley surface of the specimen brings about a retraction of the round bandsaw blade from the end of the workpiece. As a result, when the probe moves into a void, the blade moves oppositely, namely it retreats from the molding and when the probe detects a protrusion, the blade plunge cuts. The blade is forced to respond to the negative of the profile whereby the faithfulness of reproduction is severely impaired. For example, when the probe retreats because of protrusions on the specimen if the probe separates from the protrusion, an profile destroying plunge cut occurs in the molded workpiece.